I've been lucky enough to see a lot of animals in the wild, but platypuses always evaded me. I even lived by a river for a year, where everyone else saw them.
About a week ago I finally spotted one in a nearby lake while going for a run. It was just happily swimming, diving, surfacing, repeat. I watched it for ages.

Chipmunks did it for me. They look and act so much like cartoon critters I couldn't believe what I was seeing.